Synonyms for Two:

adj.

double (adjective)
dualistic, twinned, double-faced, dual, second, two-fold, duple, twin, two-sided, paired, bi-form, duplex, binary, duplicate, double-barreled, twice, double, dyadic, bifurcated, bilateral, two-faced.
dual (adjective)
both, either, dual, matching, coupled.
having two of something (adjective)
dualistic, bilateral, dyadic.

n.

eight, five, eleven, fifty, eighteen, cardinal number, billion, eighty, fifteen, crore. group, same. artifact (noun)
deuce.
duality (noun)
couplet, team, duet, brace, yoke, twosome, couple, dyad, doublet, pair, span, match.
duplication (noun)
bifurcation, duo.
twin (noun)
bifid.
two (noun)
deuce, cardinal, 2, ii.
two of something (noun)
deuce, dyad, brace, doublet, bifurcation, twin, span, binary, duet, double, couple, dual, team, pair.

Other synonyms:

Other relevant words:
deuce, billion, cardinal, eighteen, crore, eight, bifid, five, fifteen, ii, eighty, 2, group, eleven, same, cardinal number, fifty.